Using the Pen tool,cut out the angel from the background and paste it into your file.

You can see that our image has sharpen margins.To smooth them,click on the image layer and add a layer mask(Layer->Layer Mask->Reveal all).Set the foreground color to black and using the Airbrush Soft Round brush,make the margins a little bit smoother.

Now our image should look like this:

To make it more colourful duplicate the layer and set the blending mode for this new layer to Soft light.

Let`s make some clouds.I`ve found some nice clouds on DeviantArt.My opinion is that if you want some nice stuff like brushes or pictures,DeviantArt is the best solution.

Place the clouds on your picture until you get the best result.

My picture looks like this:

We`re gonna make now a divine light coming from the sky.Select the first layer(the locked one) and go to Filter->Render->Lightning Effects and apply the next settings:

We`ve just obtained the final result.Now,our image is ready and looks like this: